A method of masked dye diffusion to locally pattern the emissive color of o
rganic light-emitting devices (OLEDs) over a large area is introduced. By u
sing a large-area diffusion source, which may be a spin-coated doped polyme
r film, the entire process of masked diffusion of dye into a polymer film o
f an OLED to create an integrated three-color device has been demonstrated
at atmospheric pressure. The materials used to demonstrate this method are
the polymer poly(9-vinylcarbazole) combined with electron transport molecul
es, and the dyes bimane, coumarin 6, and Nile red. (C) 1999 American Instit
ute of Physics.